British Gas late payment on Credit File

Hi all

Moved house unexpectedly at the end of July and informed British Gas we'd be switching supplier, they said told me my final bill would be forwarded to my new address. I received a letter picked up the phone and paid the bill on 4th Sept.

Fast forward to the other day and I saw my credit rating has dropped 114pts - upon further investigation BG have slapped a late payment on there.

Ive spoken with them over Twitter (messages) explained that this is a mistake i paid as soon as i recieved the letter. They said my file has "paperless billing" on there and an email was sent out on the 1st Aug, then a reminder email on the 16th. I didnt receive either email and ive checked spam. Ive asked for it to be adjusted for goodwill as i was a good customer for 4+ years always paying on time etc.

they've said "It's not a matter of a 'goodwill adjustment', we're not able to tell the credit reference agency that the payment wasn't late as that’s not true information. I simply don't have the power to change it."

Is there anything that can be done? I was late paying this by 5 days because of a simple miscommunication. Ive worked hard getting my credit score up and im on the verge of applying for my family's first home.